The present invention relates to video viewing, and more particularly to a multiple video preview system for a video production switcher or video effects device for observing the video simultaneously at several points within the switcher or effects device.
Users of video production switchers often need to preview the result of a next transition that the switcher will make. It is particularly useful for setting up keys and other effects. This preview capability is built into most switchers. However users often also want to see the video "inside" the switcher at several different locations. For example in a switcher with multiple mix/effects sections and a downstream keyer they would like to view the clean output of each of the mix/effects sections, the preview or next transition output of each mix/effects section, and the downstream keyer. Live production particularly requires extensive preview capabilities. To provide several different preview outputs at the same time requires multiple preview circuits inside the switcher.
Previously viewing of multiple preview outputs also has required multiple output amplifiers in the switcher together with multiple cable connections to multiple video monitors. The monitors are expensive and bulky. Alternatively each preview output may be switched one by one to a single monitor, but for live production this is time consuming and impractical as decisions have to be made rapidly.
Therefore what is desired is a multiple video preview system that allows multiple preview outputs to be viewed simultaneously on a single monitor.